DESCRIPTION (From Application): This is a revised application for a UPR MIRT Program to include 11 research trainees, 9 of which will be undergraduates, with the rest being doctoral and/or medical students or resident fellows. Two young faculty members will also be included for training. The UPR is the premier institution of higher learning for minority Hispanic students in the United States, and is first in the nation in graduating Hispanic Ph.D.s. The theme is around the broad area of international health problems focusing around molecular and immunological aspects of tropical medicine and parasitology, which are health problems that affect the populations of developing countries. The European and Australia performance sites are of those currently or prospectively collaborating with faculty at the University of Puerto Rico Medical Sciences and Rio Piedras campuses. These include laboratories in Salamanca, Valencia, Valladolid, & Gran Canaria in Spain, Edinburgh & Cambridge in the UK, Heidelberg, Germany, and Monash, in Clayton, Victoria, Australia. Training periods of 3-6 months with these outstanding investigators are contemplated.